Symmetricom Time Server Manual Do Utilizador

Chapter 4: Serial or Telnet I/O Functions

Use Burn Host Lock to display whether or not software upgrades via serial or Telnet 
connections can be performed in the normal mode.

To display the burn host lock state, send the following command:

An example unit response:

BURN_DISABLE_BIT = 0

If the lock is set to 1, upgrading is not possible via serial or Telnet connections in the 
normal mode (the burn host lock has been set). If the lock is set to 0, upgrading is possible 
(the burn host lock has been reset).

Use Burn Host Lock Set to prevent unauthorized upgrading of software via serial or Telnet 
connections.

To set the burn host lock, send the following command:

The unit responds:

Are you sure? (y/N)

If you answer “y” and press Enter, the unit executes the command.  

As a safety feature, after sending this command, you have 10 seconds to respond 
affirmatively (enter the letter “y”) to the confirmation prompt, after which the unit 
executes the command and resets.  Within that 10 second time period, any other response, 
including no response, results in the unit canceling the command.

Unit example execution:  

BURN_DISABLE_BIT = 1

Use Burn Host Lock Reset to reset the lock and allow software upgrades via serial and 
Telnet connections. You must be in bootloader mode to access this function.

To reset the burn host lock, send the following command:

The unit responds:

Are you sure? (y/N)

If you answer “y” and press Enter, the unit executes the command.